Bordignon of Italy are world-leaders in the design and manufacture of Wire Die-Springs. Their latest product is the 'supreme' load spring termed by them as 'Black'. It has been produced from such a big rectangular section of flat wire through the process of Cold-Coiling as never done before anywhere else in the world. They have an international patent for these springs, in U.S.A., Europe and Japan. The maximum compression of the free length is of about 11%. These springs are available in external diameters (diameter of the hole) ranging from 10 mm to 38 mm and in free-lengths ranging from 20 mm to 200 mm as per the size selection table.BLACK springs have been produced mainly to substitute Gas Springs, Polyurethane Springs and Disc-Springs (Belleville washers) in force categories of 100. 250, 350, 500, 1,000, 1,500 and 2,000 daN.These springs can be used also as 2-in-1 (a small Black spring inside a larger Black spring) for increase in the load-carrying capacity. In this way, the maximum load-capacity of springs meant for 32 mm housing dia and free-length of 100 mm can be raised by upto 20% (from 1,500 daN to 1,850 daN) and of springs meant for 38 mm housing dia and free-length of 100 mm too can be raised by upto 20% (from 2,000 daN to 2,500 daN). Wire springs can tolerate much higher temperatures of upto 125C as compared to gas springs which can resist only upto 70C or the presence of lubricants as compared to polyurethane springs and last much longer than disc (Belleville) springs. Wire springs require no maintenance.These springs were first introduced at the Euro Blech Fair 2010 in Germany. These are being supplied by us in India in rupee-payment.